Hydraulic brake fluid composition



tamed Mar. 18, 1941 2,235,754

HYDRAULIC BRAKE FLUID COMPO S ITION Thomas J. Bagley, Haddoniield, N. J., assignor to R. M. Hollingshead Corporation, Camden, N. L, a corporation of New Jersey No Drawing. Application May 27, 1938, Serial No. 210,487

5 Claims. (01.25241) The present invention relates to certain new In modified embodiments of the present invenand useful hydraulic brake fluids, particularly tion, soyabean oil, corn oil, and palm oil may for the hydraulic braking systems of automobiles, also be used in forming the neutral salt of the and has for its object the provision of a fluid fatty acid.

which will have a suitably low freezing point and In forming the neutral salt of the fatty acid a suitably high boiling point and low vapor preswith caustic potash or caustic soda, the resultant sure, which will not have any deleterious action neutral salt may containasmall amount of water. onthe metallic and non-metallic parts of the that is, about water. This water may be hydraulic brake system with which it comes in eliminated, however, by heat. In using the di- 10 contact, which will not deteriorate in any way, ethanol'amine or triethanol amine, the resultant 1 and which will possess suitable lubricating qualineutral salt of a fatty acid will be generally ties and tend to maintain a comparatively uniwater-free.

form viscosity and will not tend to leak out. It is also found that the triethanol amine will With the above and other objects in view, the also act in the resultant composition as a rust present invention consists of a novel composition inhibitor.

of matter including a soap and an alcohol. The present invention may be embodied in l have found that certain salts of fatty acids, other specific forms without departing from the as for instance, that produced by the combination spirit or essential attributes thereof, and it is of ricinoleic acid and an alkali such as caustic therefore desired that the present embodiments potash or diethanol amine or triethanol amine be considered in all respects as illustrative and 20 or caustic soda, dissolved in an alcohol, will pronot restrictive, reference being had to'the ap duce a hydraulic brake fluid composition highly pended claims rather than to the foregoing dedesirable and useful and possessing all the qualiscription to indicate the scope of the invention. ties hereinabove set forth. Having thus described the invention, what is $5 In the preferred embodiment of the present hereby claimed as new and desired to be secured invention, ricinoleic acid is combined with enough by Letters Patent, is: 1 alkali, such as caustic potash or caustic soda or 1. A hydraulic brake fluid composition contriethanol amine or diethanol amine, to produce a sisting of from 15 to 40% of a neutral triethanol substantially neutral product. The resultant amine salt of ricinoleic acid and the balance an 0 product is then dissolved in ethyl alcohol or butyl alcohol of the group consisting of ethyl alcohol, alcohol or di-acetone alcohol or acetone or isobutyl alcohol, di-acetone alcohol, isopropyl alpropyl alcohol or methyl alcohol, or some of the coho], methyl alcohol, ethyleneglycol and diethylmore fluid dihydric alcohols having low freezing eneglycol. point, such as ethylene glycol and diethylene- 2. A hydraulic brake fluid composition consisttglycol. The proportion in using ethyl alcohol and ing of a neutral triethanol amine salt of ricinoleic butyl alcohol is about 25%, more or less, of the acid and ethyl alcohol. neutral mixture, to 75%, more or less, of the 3. A hydraulic brake fluid consisting of from alcohol. These proportions may be varied ac- 5 to of a neutral tri-ethanol amine salt of cording to the freezing point or boiling point ricinoleic acid and the balance alcohol. limits desired. From 5 to 40% of a neutral salt 4. A hydraulic brake fluid consisting of a new 40 of ricinoleic, acid, and the-balance .a1cohol,-have tral triethanol amine'salt of ricinoleic acid disbeen found to be the optimum range; although solved in butyl alcohol. I prefer from 10 or 15 to 40% of neutral salt of 5. A hydraulic brake fluid consisting of a neuricinoleic acid. g I tral triethanol amine salt of ricinoleic acid dis- The product may also be'made by hydrolizing solved in iso-propyl alcohol.

and breaking down castor oil and then neutralizif ins the 'resultant ricinoleicfacidfidthe'manner THOMAS J. 'BAGLEY. aboveindicated. 

